Actuation mechanism for flexible endoscopic device

ABSTRACT

An endoscopic accessory medical device is provided. The device can include a handle, a flexible shaft, and an end effector. The handle can include an actuator for operating the end effector through a wire or cable pulling member that extends through the flexible shaft. The handle and actuator can be operable with a single hand, such that the operation of the end effector can be accomplished with the same hand that is used to hold the handle and advance the end effector through an endoscope. The handle can include an actuation mechanism that is decoupled from operation of the end effector when the actuator is in a first open position, which becomes operatively coupled to the end effector when the actuator is moved to a second position, such as by squeezing the actuator, and which operates the end effector when the actuator is moved further to a third position.

FIELD OF THE INVENTION

The present invention relates, in general, to medical devices, and moreparticularly to handles on endoscopic and surgical accessories.

BACKGROUND OF THE INVENTION

Endoscopists typically perform diagnosis and therapy using a flexibleendoscope such as a gastroscope, colonoscope, enteroscope, cystoscope,or other types of endoscopes. The endoscope provides the endoscopistwith the ability to visualize the inside of a lumen, and is oftendesigned with an integral working channel through which small accessorydevices may be passed to perform therapy at various tissue sites withina body.

Guiding the flexible endoscope to the desired location within a bodylumen requires a high level of skill. For example, navigating a tortuousbending colon or introducing a gastroscope into an esophagus can be adifficult and time-consuming part of a procedure. Therefore, much of theendoscopist's skills are related to using and handling the endoscope.Unlike certain procedures in laparoscopic surgery where an assistant mayhold the camera, use of a gastroscope typically requires that theendoscopist always maintain the scope with at least one hand, leavingonly one hand to introduce and operate accessories through the integralworking channel of the scope.

Current handle designs typically require the use of an operator's thumbto actuate the end effector. Among the current designs are pistol grips,syringe grips, and scissor grips. These existing designs do not allow anendoscopist to both feed and operate (e.g. slide, open, close, actuate,etc.) the accessory being used with the endoscopist's single free hand.

Therefore, an assistant is typically used to operate (slide, open,close, actuate) an accessory such as a forcep or snare to take biopsiesor remove polyps. For example in a gastrointestinal procedure, a righthanded endoscopist typically holds the endoscope controls in his/herleft hand and may advance an accessory device into the working channelof the endoscope with the right hand by grasping the shaft of theaccessory. An assistant, who stands close to the endoscopist, isemployed to open, close, or otherwise acuate the accessory when giventhe verbal direction by the endoscopist. The endoscopist feeds theaccessory to the desired tissue area using a combination of articulatingthe endoscope with the left hand and feeding the accessory forward withthe right hand, and verbally signals the assistant when to open or closethe jaws to remove a portion of tissue.

Although this procedure using an assistant is used, there may be delaysor miscommunication between endoscopist and assistant as to when orwhere to operate an accessory that results in procedure delays,misdiagnosis, or incomplete tissue removal. Another issue thatoccasionally arises when using an endoscopic accessory is that windingor otherwise positioning a long, flexible accessory instrument in atortuous path can result in a reduction in ability to open or close theend effector at the distal end of the device. This loss in the abilityto open or close the device results from the free floating pull cable(typically inside a long flexible device) being placed in tension as theshaft is wound, causing the end effector to partially closeindependently of actuation of the handle. Such limitations in the endeffector motion may reduce the ability to perform a procedure, or reducethe force with which jaws close, affecting an operator's ability tosample tissue adequately.

SUMMARY OF THE INVENTION

Applicants have recognized the desirability of having a handle andactuator that permits the endoscopist to both feed and operate thedevice with a single hand, which in turn can help minimize the potentialfor miscommunications with an assistant.

Applicants have also recognized the need for an actuating mechanism thatpermits a relatively long, flexible accessory instrument to be placed ina tortuous path, without losing the full range of acuation of the endeffector due to movement of an internal pull member such as a pull cableor wire relative to an outer sheath of a flexible member, and whichprovides adequate stroke length to completely close the end effector ofthe accessory instrument, even when it is placed in a tortuous path.

In one embodiment, the present invention provides a handle for use withan endoscopic device. The handle is adapted for use with a single hand,the handle comprising: a housing adapted for gripping in the palm of auser's hand; and an actuator for actuating an end effector associatedwith the endoscopic device. The actuator is operable by one or morefingers of the same hand, wherein the actuator is operable without theuse of either of the thumb and index finger of the same hand, andwherein the thumb and index finger of that hand are free to advance aportion of the endoscopic device through an endoscope.

In another embodiment of the present invention, a method of operating anendoscopic device is provided, including the steps of: holding a handleof the device between the palm and at least one finger of the hand otherthan the index finger and thumb; holding a portion of a flexible shaftextending from the handle between the thumb and another finger of thesame hand holding the handle; advancing the flexible shaft using atleast the thumb of the same hand holding the handle; and operating anactuator associated with the handle with the same hand holding thehandle without using the thumb of that hand to operate the actuator.

The present invention also provides a method comprising the steps of:providing an endoscope having at least one channel; providing anendoscopic accessory comprising a flexible member (such as a flexibleshaft), a handle associated with a proximal end of the flexible member,and an end effector associated with a distal end of the flexible member;steering the distal end of the endoscope with one hand; holding thehandle of the endoscopic accessory in the other hand; advancing theendoscopic accessory through a channel of the endoscope with the handholding the handle and while holding the handle; and actuating the endeffector of the endoscopic accessory with the hand holding the handlewhile holding the handle.

The present invention also provides a medical device comprising: aflexible member, such as a flexible shaft with a pulling member (such asa wire or cable) movable therein; an actuating mechanism operativelyassociated with a proximal end of the flexible shaft; and an endeffector associated with the distal end of the flexible shaft. The endeffector can be operatively associated with a distal end of the pullingmember; and the actuator mechanism can have a first configuration inwhich the actuator mechanism is decoupled from the pulling member, and asecond configuraton wherein the actuator mechanism becomes operativelycoupled to the pulling member to operate the end effector. Decouplingthe actuator mechanism from the pulling member in the firstconfiguration enhances the ability of the flexible shaft to take on atortuous path while maintaining good end effector actuation.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. The invention itself, however, both as toorganization and methods of operation, together with further objects andadvantages thereof, may best be understood by reference to the followingdescription, taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is an illustration of a medical device handle 40 associated witha proximal end of a flexible endoscopic accessory 124 having a pair ofbiopsy jaws 151.

FIG. 2 shows a cross section of a known flexible shaft construction.

FIG. 3 illustrates an arrangement of handle 40 in an endoscopist's handthat allows actuation of biopsy jaws 151 between the palm 112 and fourthfinger 115 of a user and forward advancement of the flexible shaft withthe user's thumb 120 and index finger 105 of the same hand.

FIG. 4 is an illustration of an endoscopist's hand positions while usingan endoscope 128 and endoscopic accessory 124 with handle 40.

FIGS. 5, 6, and 7 illustrate alternative embodiments of handle 40 withvarious means for attaching handle 40 to a hand without gripping withfingers.

FIG. 8 is a sectional view of one embodiment of an actuation mechanism80 within handle 40 of FIG. 1 in a completely open position.

FIG. 9 is a cross section view taken at line 9-9 of FIG. 8 showing theorientation of a torsion spring 77 and a wire sleeve 95 when an actuator50 is in a completely open position.

FIG. 10 is a sectional view of actuation mechanism 80 within handle 40in a position that begins engagement of torsion spring 77 to wire sleeve95.

FIG. 11 is a cross section view taken at line 11-11 of FIG. 10 showingtorsion spring 77 engaging wire sleeve 95.

FIG. 12 shows an isometric view of torsion spring 77 and wire sleeve 95when actuator 50 is in the position shown in FIG. 10.

FIG. 13 is a sectional view of actuation mechanism 80 within handle 40when actuator 50 is in the completely closed position.

FIG. 14 is a detail cross section view of a ratchet mechanism 110showing the proximal portion of handle 40 including a return spring 87seated within a release 44.

FIG. 15A-I illustrates various endoscopic end effectors.

FIG. 16 illustrates a portion of an actuation mechanism in analternative embodiment of the present invention employing interlockingfeatures such as teeth to couple the actuation mechanism to the pullingmember.

FIG. 17 illustrates a portion of an actuation mechanism in analternative embodiment of the present invention employing a collet tocouple the actuation mechanism to the pulling member.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a novel medical device handle 40 according to the presentinvention associated with the proximal end of an endoscopic accessoryinstrument 124. The accessory 124 illustrated in FIG. 1 includes abiopsy jaw pair 151 (also referred to as biopsy jaws 151) at the distalend of the accessory 124. For illustrative purposes, the descriptionthat follows uses biopsy jaws 151 as an example of a suitable endeffector on endoscopic accessory 124, but it is apparent to thoseskilled in the art that handle 40 may be used with other accessoryinstruments having other end effectors or other devices positioned atthe distal end of accessory 124 for providing diagnostic and/ortherapeutic function(s), such as, but not limited to, biopsy forcepssuch as biopsy jaws 151, grasping forceps, surgical scissors,extractors, washing pipes and nozzles, needle injectors, non energizedsnares, and electosurgical snares.

FIGS. 15A-15I illustrate various end effectors. FIG. 15A illustrates abiopsy forceps for taking and removing from the body a tissue sample,similar to the biopsy jaws 151 illustrated in FIG. 1. FIG. 15Billustrates a tissue grasper, which can be used to grasp tissue forpulling or moving the tissue. FIG. 15C illustrates surgical scissors forcutting tissue. FIG. 15D illustrates a surgical snare, which can be anelectrosurgical snare or a non-energized snare. FIG. 15E illustrates atissue coagulation electrode of the type having suction holes at thetip. FIG. 15F illustrates a spraying nozzle, which can be used forwashing a tissue site or delivering a diagnostic or therapeuticsubstance to a tissue site. FIG. 15G illustrates a magnetic extractorfor extracting magnetic objects from a tissue site. FIG. 15H illustratesa needle injector for providing injection capability at a tissue site.FIG. 15I illustrates a retrieval basket for capturing and retrieving atissue sample from inside the body. The end effector employed at thedistal end of accessory 124 can be used for various diagnostic and/ortherapeutic procedures, including without limitation cutting tissue,grasping tissue, piercing tissue, injecting tissue with a substance,extracting objects from tissue sites, visualizing or magnifying a tissueimage, and cauterizing or ablating tissue.

Generally, handle 40 can include a housing 47, an actuation mechanismincluding an actuator 50 shown in the form of an actuator lever, and anattachment 57 to a flexible member, such as flexible shaft 65. Otherembodiments of handle 40 may include a swivel ring 55 and a release 44.Flexible shaft 65 can be at least 0.5 meters long, and more particularlyat least about 1 meter long.

The housing 47 can have a generally smooth shape that is comfortable tohold within a human hand during an endoscopic procedure, such as but notlimited to: a barrel shape, torpedo shape, or generally cylindricalshape, which shapes can have a longitudinal axis, with one or both endsbeing rounded or tapered so that the portion of the handle having themaximum diameter (or other maximum width dimension) is positionedintermediate the proximal and distal ends of the handle. The housing 47can be shaped to fit in the palm of the users hand such that the thumband index finger are positioned away from the attachment 57 to theflexible shaft 65.

Housing 47 can have a hollow shell construction formed of two halfshells. Housing 47 supports the actuation mechanism (shown in moredetail in FIGS. 8 through 12) that causes biopsy jaws 151 to open orclose when actuator lever 50 is moved. Housing 47 may be molded, cast,or machined from any suitable material, including without limitationplastics or metals. For example, housing 47 can be formed frompolycarbonate (such as is available as Calibre 2061 from Dow Plastics,Midland, Mich.) or aluminum. Housing 47 may also comprise a relativelysoft, comfortable gripping surface made from a material such asSantoprene 281-55 Rubber available from Advanced Elastomer Systems,Akron Ohio on the exterior surface of housing 47 to facilitate holdingby the endoscopist.

Actuator 50 can be pivotably supported adjacent the end of housing 47associated with flexible shaft 65, which end can be the distal end ofthe housing 47.

Acuator 50 can be pivotably supported at an actuator pin 62 (see FIG.8). Actuator 50 may be made from any suitable material, including aplastic such as polycarbonate, or metal such as aluminum. In oneembodiment, the position of actuator 50 can be biased (such as with aspring) to be in an open position so that squeezing of actuator 50toward housing 47 causes the actuation mechanism to close biopsy jaws151.

The distal end of housing 47 includes attachment 57 to flexible shaft65. Attachment 57 may include a strain relief component that preventsflexible shaft 65 from breaking at the point where shaft enters or isotherwise connected to housing 47. For example, a rubber or rubber likeboot 67 may be used for this purpose at attachment 57. Boot 67 may bemolded from a soft flexible material such as Silastic silicone Q7-4535(Dow Corning Midland, Mich.).

Still referring to FIG. 1, swivel ring 55 is one embodiment of a meansfor holding handle 40 without gripping with fingers. Swivel ring 55 maybe attached to a proximal end of housing 47, and may also be molded,cast, or machined from a plastic or metal such as those described foruse in housing 47. A swivel joint 59 may allow a full 360 degreerotation of swivel ring 55 with respect to housing 47 for ease ofmanipulation within the hand. Other embodiments of a means for holdinghandle 40 to a hand without gripping with fingers are shown in FIGS. 5,6 and 7.

A release 44 can be provided for opening biopsy jaws 151 if a ratchetmechanism or other equivalent means is employed to maintain biopsy jawsin a closed configuration when actuator lever 50 is partially orcompletely depressed. A ratchet mechanism 110 is illustrated in FIG. 14.Release 44 can extend from the proximal end of housing 47. In theembodiment shown in FIG. 14, when actuator lever is 50 is depressed,ratchet mechanism 110 is engaged to hold biopsy jaws 151 closed orpartially closed. Release 44, which may be in the form of a button,slider, switch, or other suitable release member, is used to disengageratchet mechanism 110 to allow actuator 50 and biopsy jaws 151 to open.

FIG. 2 illustrates a suitable construction of flexible shaft 65 which isknown in the art for use with flexible endoscopic instruments. Theflexible shaft comprises an outer sleeve 30, a tightly wound spring 32,and a pulling member such as a pull cable 99. Pull cable 99 floatsfreely within the inner diameter of spring 32. Tension applied to cable99 can be used to actuate certain end effectors which may be disposed atthe distal end of shaft 65 (e.g. to close biopsy jaws, forceps jaws,etc.). In embodiments of the present invention, the proximal end of pullcable 99 can be operatively associated with the actuation mechanismwithin the housing 47, and a distal end of pull cable 99 can beoperatively associated with an end effector such as biopsy jaws 151.

FIG. 3 shows housing 47 comfortably residing in an endoscopist's hand.Housing 47 and actuator lever 50 are positioned between the palm 112 andthe forth finger 115 and fifth finger 118 of that hand to actuateclosure of the end effector, with the thumb 120 and index finger 105positioned above (proximally of) the actuator lever 50 in FIG. 3. Athird middle finger 108 of the same hand may be inserted through swivelring 55 to enable the user to hold the endoscopic device 124 withoutgrasping the handle 47 with multiple fingers, so that other fingers arefree for other actions. The thumb 120 and index finger 105 of the samehand are free to pinch shaft 65 of the endoscopic accessory 124 foradvancing it through a working channel 133 of an endoscope 128 (shown inFIG. 4). Handle 40 is adapted to be held such that the smaller fingers(i.e. the fourth and fifth fingers 115 and 118) are positionedrelatively closer toward the distal end of the handle 40 associated withflexible cable 65, while the larger fingers (i.e. the thumb and indexfinger) are positioned relatively closer toward the proximal end of thehandle 40. When handle 40 is grasped between the palm and smallerfingers of the hand, the thumb of that hand points in a generallyproximal direction, and generally opposite to the direction in whichflexible shaft 65 extends from handle 40. Also, the thumb and indexfinger are positioned proximal of the free end of actuator lever 50.

As shown in FIG. 3, shaft 65 may be formed in a loop 126 behind the handand may then be pinched in between the thumb 120 and index finger 105 tofeed forward into working channel 133. Release 44, which can be in theform of a plunger like button, resides in an area that is accessible bythumb 120 for disengagement of ratchet mechanism 110 (FIG. 14), such asat the proximal end of handle 40.

FIG. 4 depicts hand positions that may be used by a right handedendoscopist while using endoscope 128 and endoscopic accessory 124 withhandle 40. The left hand is typically used to operate an articulationcontrol 131 on endoscope 128. Endoscopists may practice extensively tohone their skills in manipulating these controls to navigate the bodylumen, such as a colon. Because the procedure success is highlydependent upon the view seen by the camera located at the distal end ofendoscope 128, the endoscopist typically does not give up control of anarticulation control 131 during the procedure. Therefore, only one handis typically available to operate endoscopic accessory 124.

Endoscopic accessories with existing handle designs, such as pistolgrips, scissor grips, or syringe grips, use the thumb 120 to operate(open/close/slide) the end effector. Therefore, the endoscopist uses hisor her free hand to feed shaft 65 of endoscopic accessory 124 throughworking channel 133 of the endoscope 128 while giving verbal cues to anassistant to open or close biopsy jaws 151. Prior handle configurationsare not used by the endoscopist to operate the end effector with thesame hand used to advance the end effector into working channel 133.Handle 40 of the present invention is useful in giving control of theadvancement and actuation of the endoscopic accessory 124 to theendoscopist, to thereby reduce or eliminate any delay ormiscommunication with an assistant.

FIGS. 5, 6 and 7 illustrate alternative embodiments of handle 40 withalternative means for attaching to a hand without gripping with fingers.FIG. 5 shows handle 40 with a strap 69 made from a durable textile, suchas nylon. Strap 69 may be tethered to housing 47 at two or more points,and may be made adjustable in size by the use of an attachment section72 of hook-and-loop material such as Velcro brand fastener. FIG. 6depicts a looped strap 75 that could be used to hold handle 40 to thehand. FIG. 7 shows another alternative of handle 40 using a malleablehook 34 that can be formed into a shape to conform to the hand so thatit can remain attached without gripping with fingers.

FIG. 8 shows a side view of a cut away of one embodiment of an actuatingmechanism which may be used to operate the end effector disposed at thedistal end of the flexible shaft 65. In FIG. 8, the actuator lever 50 isin a first position, fully open, and the actuating mechanism is shown ina first configuration, corresponding to the biopsy jaws 151 being open,and with no tension applied to cable 99 by the actuation mechanism andno engagement of the actuation mechanism with the pulling member.

The embodiment of the actuation mechanism in FIGS. 8-12 includes a drivelink 89 (also referred to as link 89), a torsion spring 77, a springblock 92, and a return spring 87. A wire sleeve 95, which is fixedlyattached to the proximal end of pull cable 99, can be engaged by torsionspring 77 when spring 77 is compressed.

Also shown are components of a ratchet mechanism 110 that may be used tohold biopsy jaws 151 closed or partially closed upon compression andrelease of actuator lever 50. Ratchet mechanism 110 includes a leafspring 85 having a pawl 36 associated with the free end of the spring85, and a release 44 to disengage pawl 36 from a rack 102 supported on aspring block 92.

Link 89 is shown pivotably connected at a first end to actuator 50 by alink pin 64. The opposite second end of link 89 is shown operativelyassociated with spring block 92 by a distal block pin 74 extendingthrough link gripping slot 82, which slot 82 extends through link 89near the second end of link 89. As shown in FIG. 12, the second end oflink 89 can have a forked or clevis like configuration, and a slot 82can be disposed in each fork or clevis arm, with each slot 82 engaging apin 74. Link 89 may be machined or cast from metal such as stainlesssteel or aluminum.

Link 89 transfers the force from actuator 50 to first cause closure oftorsion spring 77 about wire sleeve 95 (which sleeve 95 is fixed to theproximal end of pull cable 99), and then to provide sliding of springblock 92 toward the proximal end of handle 40, ultimately to provideclosure of the end effector operatively associated with the distal endof flexible shaft 65. A stroke length applied to pull cable 99 ofapproximately 0.200 inches to 0.600 inches is appropriate for use inclosing biopsy forceps 151. In one embodiment, the actuating mechanismcan provide a range from about 0.400 to 0.450 inches for closing biopsyforceps 151.

Referring to FIG. 9, when actuator lever 50 is in the first openposition, (as shown in FIG. 8), there is a clearance 26 between wiresleeve 95 and the inner diameter of torsion spring 77. The magnitude ofthis clearance may be about 0.025 to about 0.050 inch in one embodiment.This clearance 26 allows wire sleeve 95 to float freely inside torsionspring 77 as flexible shaft 65 is wound into a tortuous path. Becausewire sleeve 95 is decoupled from torsion spring 77 until actuator lever50 is depressed a predetermined distance corresponding to closure of thespring 77 on sleeve 95, the actuation mechanism does not hold orotherwise constrain sleeve 95 and pull cable 99 when the actuator lever50 is in the open position. As a result, flexible shaft 65 can be woundor otherwise placed in a tortuous path without causing closing of thebiopsy jaws 151. Cable 99 and sleeve 95 are not mechanically coupled tothe actuation mechanism with lever 50 in the full open position. Withlever 50 in the full open position, and cable 99 and sleeve 95 can moveproximally or distally relative to handle 40 and outer sleeve 30. It isnot until lever 50 is closed sufficiently such that spring 77 gripssleeve 95 that the proximal end of cable 99 and sleeve 95 areconstrained by the actuation mechanism. Therefore, a full throw of lever50 provides a full range of motion of the end effector even when shaft65 is placed within a tortuous path.

Torsion spring 77 can have a wire diameter of about 0.025 inch to about0.060 inch, and in one embodiment is made from spring wire having adiameter of 0.0385 inch. Torsion spring 77 may be coiled about 3 timesand the inner diameter of the coil may range from 0.100 inch to 0.500inch in the non compressed state, with the uncompressed inner diameterbeing about 0.250 inch in one embodiment. The spring arms extending fromeach end of the coil may have a length from 0.100 inch to 0.400 inch sothat they may be fixed or moved to cause the spring inner diameter tochange. When the arms are squeezed, the inner diameter of the springcoil is reduced, such as from 0.250 inch to about 0.200 inch, or by aninner diameter reduction of about 0.050 inch. In such an embodiment, asleeve 95 residing within the coil and having a diameter slightlygreater than about 0.200 inch can be gripped by the compressed spring inthis embodiment. One suitable spring 77 is available from theMcMaster-Carr (Aurora, Ohio) catalog as part number 9287K81.

FIG. 10 shows a side cut away view of the actuator lever 50 in a secondpartially closed position, and the actuation mechanism in a secondconfiguration, with torsion spring 77 just gripping wire sleeve 95 (seeFIG. 11), so that the actuation mechanism engages the pulling member. Aspring compression slot 91 in link 89 is present to capture a closurearm 135 of torsion spring 77, so that as actuator 50 is depressed, link89 slides down on distal block pin 74, and compresses torsion spring 77(see FIG. 11). A fixed arm 137 of torsion spring 77 can be fixed to,disposed in, or otherwise constrained by spring block 92.

FIG. 12 is an isometric detail view of wire sleeve 95, spring block 92,torsion spring 77, and clevis arms of link 89. Wire sleeve 95 can have agenerally cylindrical body having an outer diameter that allows it tofit within torsion spring 77 when spring 77 is not compressed. Thedistal end of wire sleeve 95 can be joined to the proximal end of pullcable 99 by any suitable means, such as by a set screw 38 (shown in FIG.8), or by crimping, welding, brazing, or other fastening means. Sleeve95 provides a larger diameter gripping surface than would be provided bypull wire 99. A shoulder 42 disposed on wire sleeve 95 provides asurface against which return spring 87 can be compressed, so thatactuator 50 is biased to an open position when not actively squeezed orheld by ratchet mechanism 110. Wire sleeve 95 may be cast or machinedfrom a metal such as stainless steel or aluminum. In the embodimentshown, the diameter of the distal portion of wire sleeve 95 whichresides within torsion spring 77 may be about 0.220 inch, the shoulder42 may have a diameter of about 0.3250 inch, and the proximal portionthat fits within return spring 87 may have a diameter of about 0.1250inch.

Spring block 92 may be made from a dense plastic such as Ultem 2100(General Electric Plastics, Pittsfield, Mass.), or from metal such asstainless steel. As actuator 50 is depressed, spring block 92 isconstrained to move toward the proximal end of handle 40 along thelongitudinal axis of the handle 40, with proximal block pins 79 anddistal block pins 74 riding in parallel grooves or other suitablefeatures which can be formed on the inside surface of housing 47. Springblock 92 may include a rack 102 comprising a plurality of teeth 97. Asspring block 92 slides back toward the proximal end of housing 47, rack102 is engaged by pawl 36 of leaf spring 85 to hold the end effector ina closed or partially closed position. Leaf spring 85 is formed fromspring steel, and may have a thickness of about 0.02 inch.

FIG. 13 is a cut away view of handle 40 showing a third configuration ofthe actuation mechanism when actuator 50 is in a third, completelyclosed position. This view shows wire sleeve 95 translated along theaxis of the handle 40 toward the proximal end of handle 40, with theactuator mechanism applying the maximum tension on pull cable 99 toclose the end effector. In FIG. 13, return spring 87 is compressed, anda distal return spring 70 is stretched, both of which act to biasactuator lever 50 toward the open position. If a ratchet mechanism 110is not employed, the actuator lever can be held in the closed positionby the palm and small finger 118 to keep the end effector closed.

Return spring 87 may be made from 0.016 inch wire and have an outerdiameter of about 0.200 inch. A suitable return spring 87 is availablefrom McMaster-Carr (Aurora, Ohio) as part number 9657K66. Distal returnspring 70 may also have a wire diameter of about 0.016 inch, and anouter diameter of about 0.125 inch. A suitable distal return spring 70is available from Lee Spring Company (Brooklyn, N.Y.) as part numberLE-016A-002.

FIG. 16 illustrates an alternative embodiment for providing coupling anddecoupling of the actuation mechanism with the pull member. In FIG. 16,actuator lever 50 is pivotably pinned with respect to housing ( housing47 represented schematically in FIG. 16) such as by pin 62, andpivotably pinned to link 189 and link 289 at pin 291. Link 289 is shownpivotably pinned to the housing by pin 287. Link 189 extends fromactuator lever 50 to be pivotably pinned to sleeve engagement member 177at pin 292. Sleeve engagement member 177 has teeth 277 (or othersuitable surface features) for engaging complimentary teeth 295 on wiresleeve 195. Wire sleeve 195 is joined to the proximal end of pull wire99, such as with a set screw or by bonding wire 99 to sleeve 195. Wiresleeve 195 is constrained by guide grooves, pins, or other suitablemeans such as can be provided on the inside of housing 47, so thatsleeve 195 moves along an axis which can be generally parallel to thelongitudinal axis of handle 40. Upon squeezing actuator 50 from an openposition to a closed position, link 189 urges member 177 downward toengage sleeve 195, against a biasing force provided by spring 377.Spring 377 can be a coil spring or leaf spring which is connected to aportion of the housing. Spring 377 acts to separate member 177 fromsleeve 195 when the actuator lever 50 is in the open position. Oncemember 177 engages sleeve 195, further closing of actuator lever 50 ( bysqueezing actuator lever 50 toward housing 47) causes link 189 to drivesleeve 195 in a proximal direction (to the right in FIG. 16) along thelongitudinal axis of the handle 40, thereby providing tension to pullwire 99.

FIG. 17 illustrates another alternative embodiment for providingcoupling and decoupling of the actuation mechanism with the pullingmember. The pulling member can include pull wire 99 and sleeve 595 fixedto the proximal end of pull wire 99. Actuator lever 50 is pivotablypinned to link 489 by pin 492. The other end of link 489 is pivotablylinked to a collet 510 at pin 494. Sleeve 95 extends through a bore inCollet 510. Collet 510 includes split collet jaws 514 and 516. Colletreceiver 530 is supported in housing 47 to move proximally against thebiasing force of spring 87. Collet receiver 530 has an inwardly facingconical surface 534. Closing actuator lever 50 causes link 489 to urgecollet 510 in a proximal direction along the longitudinal axis of thehandle 40, until collet jaws 514 and 516 engage the inclined surface 534of collet receiver 530. Upon engaging the surface 534, the jaws 514 and516 are urged radially inwardly to grip the sleeve 595. Further closureof actuator lever 50 causes sleeve 595 and pull wire 99 to move in aproximal direction (to the right in FIG. 17).

The embodiments shown employ partial closing of the lever 50 to provideengagement of the actuation mechanism with the pulling member.Alternatively, a separate actuator, such as a button, switch, or knobcould be used to provide engagement of the actuation mechanism with thepulling member.

FIG. 14 is an enlarged view of ratchet mechanism 110 of FIG. 8 in aconfiguration in which actuator 50 is in the completely closed position.Pawl 36 engages teeth 97 of rack 102 to keep tension on pull cable 99,keeping the end effector closed. To disengage pawl 36, the userdepresses release 44. Depressing release 44 causes release arm 49 toslide along leaf spring. 85. When release arm 49 passes over dimple 104on leaf spring 85, leaf spring 85 is deflected downward to disengagepawl 36 from rack 102.

During use, handle 40 may be held in a manner shown in FIG. 4. The stepsfor use of endoscopic accessory 124 with handle 40 may include placinghandle 40 within a hand, gripping flexible shaft 65 between the thumb120 and another finger on that hand, advancing the device to an areawithin the body, and actuating the actuator lever 50 between the palm112 and another finger of that hand without using the thumb 120. Thisallows single-handed use of accessory 124 while endoscope 128 isactively being held with the other hand. Accessory 124 may be fed intothe working channel 133 of endoscope 128 with the thumb and index fingerto advance the end effector to the target tissue area.

A set of instructions informing the endoscopist of the steps of use maybe packaged with the device. This may be beneficial in teaching andshowing the technique that is enabled by use of handle 40. Such aninstruction set can include a list of steps with respect to using thehandle 40. The instruction set can be associated with a medical devicehaving the handle, such as by direct association wherein the instructionset is provided with the medical device, such as in the form of printedmaterial on a label, a separate insert booklet, brochure, or sheet,recorded on a video, CD or DVD provided with the medical device, orprinted directly onto a package containing the medical device.Alternatively, the instruction set can be indirectly associated with themedical device by providing the instruction set separately from themedical device, but with reference to use of the medical device, such asin the form of materials provided on a web site, in a training brochure,video, CD, or DVD.

The handle 40 has been shown as a component of a medical device such asflexible endoscopic accessory 124. If desired, handle 40 can be providedas a stand alone product which is releasably attachable to differentflexible shafts 65 so as to be interchangeable with different endeffectors. Handle 40 and its associated flexible shaft 65 and endeffector can be made for repeated use, or can be disposable and beprovided presterilized in a suitable package.

While preferred embodiments of the present invention have been shown anddescribed herein, it will be obvious to those skilled in the art thatsuch embodiments are provided by way of example only. For example, thestructures described in relation to the present invention can beequivalently described in terms of a means for accomplishing thefunction of the structure. While the embodiments disclosed are directedprimarily to use with gastroscopes, it will be understood that theinvention is also useful with other endoscopic devices, includingwithout limitation laparoscopes. Numerous variations, changes, andsubstitutions will now occur to those skilled in the art withoutdeparting from the invention. Accordingly, it is intended that only thespirit and scope of the appended claims limit the invention.

1. A medical device comprising: a flexible shaft comprising a pullingmember movable therein, the flexible shaft having sufficient flexibilityto be formed into an operable, looped configuration during use; anactuating mechanism operatively associated with a proximal end of theflexible shaft; an end effector associated with the distal end of theflexible shaft, wherein the end effector is operatively associated witha distal end of the pulling member; wherein the actuator mechanism has afirst configuration in which the actuator mechanism is decoupled fromthe pulling member, and a second configuration wherein the actuatormechanism becomes operatively coupled to the pulling member to operatethe end effector; wherein the actuator mechanism comprises an actuatormovable from a first position wherein the actuator mechanism isdecoupled from the pulling member to a second member wherein theactuator mechanism becomes operatively coupled to the pulling member;wherein the actuator is movable from the first position to the secondposition by squeezing with a single hand; wherein the actuator ismovable from the second position to a third position wherein the endeffector is operated.
 2. The device of claim 1 wherein the actuatingmechanism comprises a resilient member for operatively coupling theactuation member to the pulling member.
 3. The device of claim 2 whereinthe resilient member comprises a spring.
 4. The device of claim 3wherein the resilient member comprises a torsion spring.
 5. The deviceof claim 1 wherein a proximal end of the pulling member is joined to arelatively larger diameter member, and wherein the actuator mechanismengages the relatively larger diameter member to provide coupling of theactuator mechanism to the pulling member.
 6. The device of claim 5wherein the actuator mechanism engages the relatively larger diametermember by gripping engagement.
 7. The device of claim 5 wherein thegripping engagement is provided by a resilient member.
 8. The device ofclaim 7 wherein the resilient member comprises a torsion spring.
 9. Thedevice of claim 1 wherein the end effector is selected from the groupconsisting of a biopsy forceps, grasping forceps, surgical scissors,extractors, and snares.